Investigation and Enhancement of a Cu-ZSM-5 SCR Catalyst Model

Abstract: The aim of this study has been to enhance LOGE's semi-detailed Cu-ZSM-5 SCR catalyst model in areas where it lacks to catch important effects. It is important to have an accurate and CPU efficient kinetic model for the catalysis in the work towards minimizing polluting NOx in the exhaust gas from diesel engines. Investigations were done on the kinetic model through a few transient experiments including NO oxidation, NH3 oxidation and a NH3 SCR experiment. The effects were tested when adjusting different parameters and an adsorption reaction for NO2 was added to the kinetic model. The simulated results were compared with experimental values. Adjustment on the kinetic parameters in the NO oxidation reaction led to a slight enhancement and results also showed that the additional adsorption reaction was sufficient to catch the desired effects. This work shows that a semi-detailed kinetic model is sufficient to capture important effects in the catalytic reduction. The model would however need to be validated through more experiments in order to generalize the results. For further improvements on the model a more complex kinetic model would be required, which could include adsorption of more species and alternative reactions.